Headspace analyzers interfaces

Zero-headspace procedures involve the collection of a soil sample with immediate transfer to a container into which the sample fits exactly. The only space for gases is that within the soil pores. The volume of sample collected depends on the concentration of volatiles in the soil. It is imperative that the container employed can be interfaced directly with the gas chromatograph. Several commercial versions of zero-headspace sampling devices are available. The sample is transported to the laboratory at 4°C, where it is analyzed directly by purge-and-trap gas chromatography (EPA 5035) or other appropriate techniques, such as vacuum distillation (EPA 5032) or headspace (EPA 5021). 

Solid-phase microextraction is an adsorption/desorption technique used to analyze the volatile and non-volatile compounds in both liquid and gaseous samples used as an alternative to the headspace, purge-and-trap, solid-phase extraction, or simultaneous distillation/extraction techniques. Analytes are thermally desorbed and directly introduced into any gas chromatograph or GC/mass spectrometry (MS) system. When coupled to HPLC with the proper interface, the analytes are washed out of the fiber by the mobile phase. 

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